Dorsal Root Ganglion Stimulation for Chronic Pelvic Pain Secondary to Endometriosis

Abstract

Introduction: Chronic pelvic pain (CPP) is a multifaceted condition that poses significant challenges in clinical management owing to its complex and varied pathophysiology, including neuropathic, somatic, visceral, and musculoskeletal components. Endometriosis is frequently associated with CPP, necessitating a comprehensive, multimodal treatment strategy. This approach typically includes physical and behavioral therapy, pharmacologic interventions, surgical management of endometriosis, and various pain-modulating procedures. Neuromodulation, particularly spinal cord stimulation (SCS), has been used in refractory cases; however, its use is often met with limited success and a notable rate of explants. This case series presents nine patients with intractable CPP secondary to endometriosis, unresponsive to conventional treatments, who were treated with dorsal root ganglion stimulation (DRG-S).

Materials and methods: Between 2022 and 2023, ten patients with severe CPP secondary to endometriosis, unresponsive to various multimodal treatments-including previous interventional pain procedures, gynecologic surgery, and in some cases, SCS-were recruited for this prospective study. Of these, nine patients underwent permanent DRG-S, with bilateral L1 and S2 DRG-S leads placed (four leads per patient). Patients were assessed for pain intensity using the visual analog scale (VAS), narcotic consumption, and quality of life (QoL) using the 12-item short-form (SF-12) survey, with a 12-month follow-up period. Nonparametric statistical analyses were conducted using SPSS.

Results: One patient was excluded from the study owing to a lack of pain relief during the DRG-S trial. The remaining nine patients underwent permanent bilateral L1 and S2 DRG-S placement. Significant improvement in pain scores was observed and sustained throughout the follow-up period (VAS 9 ± 1.5-2 ± 2.0; p = 0.003), along with a marked reduction in opioid consumption, with four patients becoming completely free of narcotics (p = 0.046). SF-12 physical scores improved by 60.2 ± 7.8 (p = 0.006), and SF-12 mental scores improved by 45.9 ± 2.76 (p = 0.01).

Conclusion: Bilateral L1 and S2 DRG-S yielded robust and sustained outcomes, including significant improvements in pain scores, reduced narcotic consumption, and enhanced QoL over a 12-month follow-up period.

Keywords: Chronic pelvic pain (CPP); dorsal root ganglion stimulation (DRG-S); endometriosis; neuromodulation; pain management.